U.S. Pat. No. 6,517,234 mentioned above discloses a technology for infusing a plurality of components into a liquid sending channel of a sample processing chip and mixing the plurality of components together in the liquid sending channel. The plurality of components is mixed together while being conveyed in a flow path called a liquid sending channel.
Such a technology for mixing a plurality of components together by use of a sample processing chip is used for mixing a target component to be processed and a diluent together in order to dilute the target component, for example. In recent years, there are demands for a technology for detecting the target component by one molecule or by one particle in a sample (hereinafter, referred to as “digital detection”). The target component is a nucleic acid, a protein, a cell, or the like, for example. In the digital detection, the target component is caused to be encapsulated by one molecule or by one particle into one droplet, for example. Since the target component is put by one molecule or by one particle into each of unit regions which are respectively composed of individual droplets, this technique is referred to as “partitioning” the target component by one molecule or by one particle. In order to partition the target component by one molecule or by one particle, it is required to dilute the target component with a dilute at a high dilution rate.